1. Field of the Invention
The present invention relates to a rivet gun, and more particularly to a rivet gun with alignment structures that include alignment elements to ensure that a handle and a pneumatic cylinder are aligned with each other at a correct rotational angle relative to an axis of the handle for quick and precise fabrication.
2. Description of Related Art
A conventional rivet gun, as disclosed by Taiwan utility model patent No. M400369, is used to rivet two boards such that the boards are securely mounted together by rivets. A rivet has a cap and a core pin. The cap is T-shaped and has an enlarged end and a mounting end. The core pin is mounted longitudinally through and protrudes out of the cap and has two ends and a ball formed on one end and adjacent to the mounting end of the cap.
A conventional rivet gun comprises a barrel, a handle, a trigger, a pin collector and a pneumatic cylinder.
The barrel has a front end, a rear end and a vise assembly that may vise and pull a core pin of a rivet on the front end into the barrel. The handle is mounted perpendicularly on the barrel and has air passageways. The collector is a jar mounted on the rear end of the barrel to collect the ejected core pins. The pneumatic cylinder is mounted movably under the handle and capable of activating the vise assembly through pneumatic and hydraulic means. Furthermore, the pneumatic cylinder may be connected to a high-pressure air source such as an air bottle to implement the ejection of the core pin.
When the rivet gun is used to rivet two pieces such as boards or plates together, a rivet is mounted through the pieces. The enlarged end of the cap of the rivet abuts an inside piece, and the front end of the barrel of the rivet gun abuts the enlarged end. The trigger is pulled to activate the vise assembly to pull a core pin on the cap into the barrel. The ball on the core pin longitudinally compresses and radially expands the mounting end of the cap into T-shape so that the expanded mounting end hooks on an outside piece to complete the riveting process. Then, the air output by the high-pressure air source flows through the barrel from the front end to the rear end and sucks the broken core pin vised by the vise assembly backward into the collector.
The handle has a flange radially formed on a bottom of the handle and a hydraulic tube mounted in the handle and having an outer thread. The pneumatic cylinder has a hollow and annular body and a top cover screwed on a top end of the annular body. The top cover presses against the flange of the handle and has a mounting hole defined therethrough such that the hydraulic tube extends through the mounting hole. A nut is screwed on the outer thread of the hydraulic tube to clamp and fasten the top cover between the flange of the handle and the nut. However, no alignment structures exist among the flange of the handle and the top cover of the pneumatic cylinder. When assembling the rivet gun, a user needs to observe through naked eyes and ensure that corresponding through holes and components on the handle and the pneumatic cylinder are aligned with one another at a correct rotational angle relative to an axis of the handle so that the handle may be pressed downward against and mounted correctly on the top cover of the pneumatic cylinder. These holes and components are hidden and cannot be observed when the handle completely presses against the top cover so that the user cannot be fully assured whether these holes and components are aligned at the correct rotational angle. Therefore, the user frequently disassembles the rivet gun and repeats assembling steps due to incorrect fabrication of the rive gun.
To overcome the shortcomings, the present invention provides a rivet gun with alignment structures to mitigate or obviate the aforementioned problems.